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UNIT D Srarns PATENT Urrrce.

JOHN H. DALZELL AND THOMAS J. MOTIGHE, OF PITTSBURG, PA.

METHOD OF CONVEYING GAS lN ANINEXPLOSIVE CONDITION.

SPECIFICATION forming part of Letters Patent No. 837,667, dated March 9 1886.

Application filed Dutember 17, IP85. Serial No. 185,972. No specimens.)

To all whom it may concern:

Be it known that we, JOHN H. DALZELL and THOMAS J. MOTIGHE, citizens of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have in vented a certain new andnseful Method forthe Conveyance of Gas in an Inexplosive Condition; and we do hereby declare the followi ngto be a full, clear, and exact description of the invention. 7

It has been found by experiment and observation that certain gases, and particularly natural gas flowing from subterranean deposits, while depending upon a supply of air to render them combustible for use, become or are rendered powerfully e plosive when the proportion ofair to gas is wi in certain limits, and when the proportion of air to gas is either above or below the limit the gas is practically non-explosive, and is therefore deprived of its dangerous properties. At the same time the inflammability of the gas and its usefulness as a heating medium remain the same, or at least sutlicient for all the purposes to which the gas is applied. In view of these facts we have devised a method whereby the conveyance of combustible gas to cities, towns, and other places of consumption and its distribution to points where it is required may be rendered entirely safe from explosion while in transit, and its usefulness and adaptability to general purposes as a fuel greatly increased.

In application for Letters Patent of the United States filed by us January 23, 1886, Serial No. 189,522, we have described a method for the conveyance and distribution of a nonexplosive mixture of gas and air, wherein the gas at or near the point of distribution is mixed or diluted with air sufficient to render it non-explosive, and the mixture then distributed or supplied to various points of consumption.

Our present invention relates to the broad idea of conveying through conduits an admixture of air and gas wherein the proportion of air is in excess of that required to render the gas explosive, and does not embrace or refer to the special method of conveying the gas from the well or source of supply to a particular point, there admixing it with air, and then distributing the non-explosive mixture.

Our invention accordingly consists in, broadly, diluting the gaswliiether the same be natural gas or artifically n'ianufactured, with sufficient proportions of air to exceed the explosive limits.

The proportions of air to be mixed with the gas to fulfill the conditions of our invention will largely depend upon the specific character of the gas; but it may be said, generally, that in case of natural gas twenty parts or more of air to one part of gas will render the mixture practically nonexplosive and enable it to be conveyed and distributed with perfect safety. The proportion of air necessary to support perfect combustion of the gas greatly exceeds the amount necessary to raise the mixture beyond or above the explosive point.

The supply of air to meet the conditions of our invention may be obtained in any convenient manner, as by locating a blower or blast apparatus in the neighborhood of the gas well or generator and leading a main into the same; or the .air may be supplied at or near the point of entrance of the main into the city, town, or neighborhood where the gas is to be consumed. In the one case the gas will be rendered nonexplosive before entering the main, or before being conveyed to the locality where it is to be consumed. In the other case the dilution of the gas will be effected after leaving the mains or principal conduits, and while on its way to the distribu*- ing pipes or branches.

The proportion of air required to take the mixture beyond the explosive limit will vary with the character of the gas according to the proportions of hydrogen and carbon present in the gas in various combinations.

A good illuminating gas made from coal may show about the following analysis as to hydrogen and carbon: hydrogen, 46.0; marshgas, (methyl hydrogen) 39.5; carbon oxide, 7.5; elayl and ditetryl, 3.8. Such a gas, generally, is said to be highly explosive when mixed with air in proportion of one of gas to seven of air. A greater proportion of air reduces this explosive property and aproportion of one to ten or twelve may be said to be practically non-explosive.

Natural gas shows an entirely different analysis. That known as the Murraysville gas,

on analysis shows the following constitution: through conduits a mixture of combustible carbonic acid, 0.6; earbonicoxide, 0.0; oxygen, 1

0.8; olefiant gas, 1.0; ethylic hydride, 5.0; marsh-gas, 67.0; hydrogen, 22.0; nitrogen, 3.0. A mixture ot'one part ol'this gas with from eight to twelve parts of air is generally considered to be destructively explosive, and therefore (i011- gerous. A greater proportion ot'air than this reduces the explosive property of the mixture, and a proportion of twentyparts of air and one ofgasispraetieally inexplosive. But even the gas foundin ditferentdistrictsshowsdifferences in constitutioxnanditisim possibletot'orn'iulate any general rule by which the minimum proportion of air can be determined. It is readily found for any particular gas by experiment. \Ve do not, therefore, coniine ourselves to any particular proportions, since, as the foregoing illustrations show, the proportions depend upon the constitution of the gas.

Having described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. The method for the safe distribution of combustible gas, which consists in conveying gas and air in such proportion as to render the mixture incapable of becoming explosive by a further admixture of air.

2. The method for theharmless distribution of gas in cities and townsto points of'consumption, consisting in conveying it through the conduits or pipes in admixture with air in such proportion that the proportion of air exceeds that at which the mixture is explosive. 3. The method of distributing combustible gas in cities and towns, consisting in admixing such gas for transmission through the distributing conduits or pipes with air in such proportion that the proportion of air is in excess of that at which the mixture is explosive. In testimony that we claim the foregoing we have hereunto set our hands this 15th day of December, 1885.

JOHN H. DALZELL. THOMAS J. Mo'liGI-IE.

\Vitnesses:

A. A. CONNOLLY, E. B. RANKIN. 

